Nail pulling machine



B. H. BLACK ET AL Oct. 28, 1941.

' NAIL PULLING MACHINE Filed April. 7,. 1941 "Will ll FHIIIIIIIIIWI Maa 4 [Ha W.

- Patented Oct. 28, 1941 NAIL PULLING MACHINE Bruce H. Black, Gary, and Clarence A. Mots, Hammond, Ind.

Application April 7, 1941, Serial No. 387,352

8 Claims.

Many establishments, including industrial plants engaged in virtually every line of operations, frequently are confronted with the reclaiming of more or less large amounts of scrap or discarded lumber, such lumber being, for example, planks from formwork, rail ties, temporary framing, bracing in railroad cars, crates and the like, which lumber frequently contains nails which must be removed in order to salvage the lumber.

Obviously, where large amounts of such material are to be handled, the removal of the nails by manual pulling is a laborious and time-consuming phase of the salvage operation, the difficulties of removal being increased very substantially by the nails frequently being bent or twisted in the tearing apart of the original structure. A

In accordance with the present invention thereis provided improved nail pulling mechanism of simple construction which is found in actual practice to facilitate greatly the removal of bent and distorted nails from discarded or scrap lumber.

A further object of the invention is to provide a machine'of the above indicated character which substantially obviates any element of danger to a worker engagedin removing nails from lumbe being salvaged.

Further objects of the invention will become apparent as the description proceeds, and the 'features of novelty will be pointed out in parreadily from a consideration of the accompanying drawing, which illustrates a machine constructed in accordance with the present invention and embodying the above generally indicated structural and functional features, it being understood that the drawing is intended to be only illustrative in character, since many actual variations in the construction may be made without in any way departing from the scope of the invention as defined by the appended claims.

In the drawing: Figure 1 represents an end elevation of an improved nail pulling machine embodying the structural features of the present invention, the machine being shown as being mounted on a suitable mounting frame;

A of the arrows, the view showing details of construction of the front or advance hold-down having imparted thereto a vertically reciprocable slow motion by means of a crank or other suitable actuating means, a "hold-down plate adapted to engage the lumber in advance of the pull-plate and having slots therein corresponding to the slots in the pul1-plate, with a second hold-down plate behind the pull-plate, these hold-down plates defining restraining .instrumentalities for holding the plank or other piece of lumber against vertical movement during the actual nail pulling operation. The lumber maybe fed to the machine by suitable feeding means which are adjustable to correspond to varying thicknesses of the lumber being handled. Such feeding means may include an adjustable feeding table having disc feeding devices or feed rollers providedwith slots in advance of the pull-plate and solid rollers after the lumber has passed the pull-plate.

plate and its corresponding feed rollers; and

Figure 4 is a sectional plan view showing additional details of construction of the pull-plate and advance hold-down plate, the view being taken on the line IV-IV of Figure 2 looking in the direction of the arrows.

Referring more particularly to the drawing, a

framework for carrying the machine is shown generally at A, the said frame including oppositely disposed angle guides 6, for the vertically reclprocable pull-plate and the actuating mechanism therefor, all of which will be referred to in greater detail hereinafter, the guidesi and 1 being mounted on suitable channel beams 9, ll of the frame A.

This actuating mechanism comprises an eccentric crankshaft 8 which is rotated very slowly by means of double speed reducing mechanism in- "shaft I! has mounted thereon a pinion II for driving a large reduction gear I9, this gear is being mounted on the crankshaft 8, a suitable However, the invention will be understood more bearing for which is indicated at on I-be'am 20, this last being mounted on I-beams 2| and 23 which span the frame channels) and II.

The crankshaft 8 carries cranklinks 24, 26 Y ample, it will be seen that the two threaded rods are indicated at 32 and 36, respectively, the rod 32 being threaded as is indicated at 34 and having an enlarged head portion 39. This head portion 30 has a hole 3| extending through it which registers with corresponding holes in the links 24 and 26. A connecting rivet 28 passes through these holes and connects the rod 32 with the links 24 and 26. a)

The other rod 36 is threaded as is indicated at 38, the threads 38 running oppositely to the threads 34 of the rod 32. The rods 32 and 36 are Joined by an adjusting nut 42 which is threaded internally to correspond with the threads 34 and 39 of the rods. Operation of the nut 42 thereby causes the rods 32 and 36 to be moved either apart or towards one another, thus adjusting the length of the stroke of the pullplate.

The rod 36 has an enlarged head portion 40 similar to the head portion 38 of the .rod 32. This head portion 40 is provided with a hole 41 extending through it which registers with corresponding, holes in the upstanding lateral slide members 45 and 48 of the pull-plate 44 which will be referred to in greater detail hereinafter. A connecting rivet 46 passes through these holes, thereby connecting the pull-plate to the rod 36.

The pull-plate itself is conveniently a-com- I posite structure, the plate 44, which is serrated by the tapered nail receiving slots 52, being reinforced by a rear web' 49 extending across the plate 44, this web terminating in the slides 45 and 48 referred to above herein, and which slide in the angle guides 6 and 1 of the mounting frame as the pull-plate moves. The web 49 im secured in any suitable manner to the plate 44.

The bottom of the plate 44 is adapted to enage the surface of a plank or other piece of timber 68 from which projects nails which are indicated at 62 and 64 as being of different sizes. The front surface of the plate 44 is provided with a plurality of tapered slots 52 which are machined to receive whatever sizes of nails are to be pulled, the nails being gripped by the tapering sides'of the slots as shown in Figures 2 and 4 as the nail bearing wood is moved into nail pulling position. The nails are gripped by the tapered slots sufliciently tightly to cause them to be pulled out upon actuation of the pull-plate. In order to accomplish this withdrawal of the nails it is necessary, however, to prevent movement of the piece of wood 68. For this purpose, hold-down plates are provided in advance of, and following,'the pull-plate.

The forward hold-down plate, designated at 54, is adapted to engage the wood 68 before the nailshave been removed by the pull-plate. Consequently, means must be providedfor avoiding obstruction of the protruding nails by the holddown plate as the wood 60 is movedinto position for the nails to be pulled. Consequently, the hold-down plate 54, which is illustrated as being a vertically disposed plate spanning the distance between the'side channels 9 and H of the frame and suitably secured thereto, is provided with a plurality. of slots 58 corresponding to the tapered 2,260,787 slots 52 in the pull-plate 44, the dimensions of the slots 58 being sufficient, however, to permit unobstructed passage therethrough of the nails.

The rear hold-down plate 51 engages nail free portions of the wood 60. Consequently, this needs to be merely a flat plate spanning the space between the side channels 9 and H and welded or otherwise secured thereto.

These hold-down plates cooperate to hold firmly the plank 60 against movement during the nail pulling operation, the plank 60 being retained against these plates and also the pull-plate 44 by a series of feed rollers, indicated at 66 and 68, which are mounted on a table 59, this table being adjustable for accommodating various sizes of wood, as will be referred to in greater detail hereinafter.

The rollers 66 and 68 hold and guide the wood as it passes the machine. The forward rollers 66 encounter the nail bearing portions of the wood, and consequently provision should be made for the passage of such nails as may have pointed ends still protruding from the underside of the wood. Therefore, it is desirable that these rollers 66 be disc rollers, as shown in Figure 3, the spaces between the discs being sufficiently wide for the unobstructed passage of the nails. So far as concerns the rollers 68, these engage only nail free wood, and consequently may be solid rollers. Obviously, rollers 66 may be grooved instead of being made into separate discs.

These rollers 66 and 68 are mounted in an adjustable table, as has been mentioned above, it being necessary to adjust this table both for the purpose of accommodating different sizes of wood and for holding the wood being handled snugly against the underside of plates 54, 44 and heads project sufficiently far to enter the tapered slots 52 when the piece 60 is inserted between the rollers 66 and the hold-down plate 54. The-adjustment of the piece 60 is performed manually and is made until the nails enter the slots 52 in the pull-plate. The spaces between the disc rollers 66 afford unobstructed passage to any portion of the nails which may still be projecting from the underside of the piece 60. With at least one nail such as that indicated at 64 gripped by the slots 52, and the piece 60 firmly heldbetween the rollers and hold-down" plates, the motor I4 is started and the pull-plate 44 is raised to the dotted line position shown in Figure 2, thus pulling outthe nail. Of course if the nails are so aligned that more than one nail. will enter the slots 52, such may be pulled out simultaneously; but in any event a suflicient number of repetitions of the operation will effect a complete, quick, and safe removal of the nails far more expeditiously than can be effected by manual labor alone, while leaving the plank or other timber in condition for ready salvage and free from splits and other damage occurring incidental to the .actual pulling of the nails.

We claim: 1. Nail pulling mechanism comprising, in comadapted to grip a nail extending from'a workpiece, instrumentalities for effecting a slow movement of the said pulling means, means for holding the workpiece against vertical movement during the pulling of the nails therefrom, the said holding means providing unobstructed passage of the nails to the said pulling means, and means plate, a vertically disposed hold-down plate in I advance of the pull-plate, the said hold-down plate having slots extending therethrough and corresponding to the slots in the pull-plate, the said slots affording unobstructed passage of protruding nails to the pull-plate, means for holding the workpiece firmly against the pull-plate and hold-down plate to secure the workpiece against vertical movement during nail pulling operations, and instrumentalities for yieldably. positioning the said last-mentioned holding means relative to the workpiece.

3. Nail pulling mechanism comprising, in combination, a mounting frame, reciprocably operable pulling means on the frame including a pull- I plate provided with tapering slots adapted to grip a nail projecting from a workpiece, a vertically disposed hold-down plate in advance of the pullplate having means affording unobstructed passage of protruding nails to the pull-plate, a horizontally disposed hold-down plate positioned rearwardly of the pull-plate, means for holding the workpiece firmly against the pull-plate and hold-down plates to secure the workpiece against vertical movement during nail pulling operations, and a means for positioning the holding means to accommodate different sizes of workpieces and for maintaining the workpiece firmly against the pull-plate and hold-down plates.

4. Nail pulling mechanism comprising, in combination, a mounting frame, reciprocably operable pulling means on the frame including a pull-plate adapted to grip a nail extending from a workpiece, mechanism for effecting a slow movement of the said pulling means, means for holding the workpiece against vertical movement during the pullingof the nails therefrom. the said means providing unobstructed passage of the nails to the said pulling means and including a table, rollers on the said table for receivingthe workpiece, the said rollers affording unobstructed passage of the nails to the pull- I ing means, and means for yieldably positioning the said table relative to the workpiece for maintaining the said workpiece secure against vertical movement during the pulling of the workpiece, mechanism for effecting a slow movement of the said pulling T posed hold-down plate means, a vertically disin advance of the pullplatehaving means affording unobstructed ing to the slots in,

passage therethrough of protruding nails to the pull-plate, a horizontally disposed hold-down plate behind the pull-plate, a table for holding a workpiece in position against the hold-down plates for enabling nails extending from the workpiece to be gripped by the pull-plate, guide rollers for positioning and holding the workpiece, certain of the said rollers being disposed forwardly of the pull-plate and others of the said rollers being disposed rearwardly of the pullplate, the said forwardly disposed rollers being discs for allowing unobstructed passage of nails therebetween to the pull-plate, and means for yieldably positioning the said rollers and table relative to the workpiece to maintain the work- 'piece tightly against the pull-plate and holddown plates during nail pulling operations.

6. Nail pulling mechanism comprising, in combination, a mounting frame, reciprocably operable pulling means on the frame including a pullplate provided with tapered slots and adapted to grip a nail extending from the workpiece, mechanism for effecting a slow movement of the said pull-plate, a vertically disposed hold-down plate in advance of the pull-plate having slots therein corresponding to the slots in the pull-plate and affording unobstructed passage to the pull plate of extending nails, a horizontally disposed holddown plate behind the pull-plate, a feeding table for the workpiece, disc rollers on the front side of the-feeding table defining a space correspondthe vertical hold-down plate, solid rollers on the feeding table disposed oppositely to the horizontal hold-down plate, and means for yieldably positioning the feeding table and rollers for maintaining the workpiece tightly against the hold-down plates for obviating vertical movement of the workpiece during nail pulling operations,

7. Nail pulling mechanism comprising, in combination, a supporting frame, reciprocably operable pulling means on the frame including a pullplate having a portion thereof provided with tapered slots adapted to grip a nail extending from the workpiece, a reinforcing web for the pull-plate extending thereacross, the said web defining slide members engaging the frame and guided thereby during movement of the pullplate, mechanism for effecting a slow movement of the pull-plate, a vertically disposed hold-down plate in advance of the pull-plate having means afiording unobstructed passage to the pull-plate ofnails extending from the workpiece, a horifor holding the workpiece plates to secure the workpiece against vertical movement during the nail pulling operations.

8. Nail pulling mechanism comprising, in combination, reciprocably operable pulling means adapted to grip a nail extending from a workpiece,1instrumentalities for effecting a slow yieldablymovement of the said pulling means, mounted clamping -means for a workpiece to clamp the workpiece against movement during nail-pulling operations, and instrumentalities for operating the clamping means, the said clamping means affording unobstructed passage of the nails to the said pulling means.

.BRUCE H. BLACK.

CLARENCE a. MOTZ, 

